The Human Body: An Orientation

Question 1

Anatomy is…

Answer 1

The study of the structure of body parts and their relationships to one another. It provides a static picture of the body’s architecture.

Question 2

Physiology is…

Answer 2

The study of the function of the body - how body parts work and carry out their life-sustaining activities. It explores the dynamic and animated workings of the body.

Question 3

The study of large body structures is called…

Answer 3

Gross, or macroscopic, anatomy.

Question 4

Explain the difference between regional and systemic anatomy.

Answer 4

In REGIONAL ANATOMY, all the structures (muscles, bones, blood, vessels, nerves, etc.) in a particular region of the body are studied at the same time (e.g., in the leg or abdomen).
In SYSTEMIC ANATOMY, body structure is studied system by system (e.g., the cardiovascular system).

Question 5

Microscopic anatomy is…

Answer 5

The study of small structures that cannot be seen with the naked eye. Subdivisions include cytology (cells) and histology (tissues).

Question 6

What branch of anatomy traces structural changes that occur through the lifetime?

Answer 6

Developmental anatomy.

Question 7

Embryology is…

Answer 7

The study of developmental changes that occur before birth.

Question 8

Define palpation.

Answer 8

Feeling organs with your hands.

Question 9

Define auscultation.

Answer 9

Listening to organ sounds with a stethoscope.

Question 10

What is the topic of study in renal physiology?

Answer 10

Kidney function and urine production.

Question 11

What is the topic of study in neurophysiology?

Answer 11

The workings of the nervous system.

Question 12

Cardiovascular physiology examines…

Answer 12

The operation of the heart and blood vessels.

Question 13

List the 6 levels of structural organisation in the human body.

Answer 13

1. Chemical level - atoms form molecules, which associate into organelles that are the basic components of cells.
2. Cellular level - the smallest units of living things.
3. Tissue level - in complex organisms (e.g., epithelial tissue, muscle tissue, connective tissue, and nervous tissue)
4. Organ level - an organ is a discrete structure composed of at least 2 tissue types that performs a specific function.
5. Organ system level - organs that work together to accomplish a common purpose.
6. Organismal level - the sum of all structural levels working to keep the organism alive.

Question 14

List the 10 organ systems in the human body.

Answer 14

Cardiovascular
Integumentary (skin)
Skeletal
Muscular
Urinary
Nervous
Endocrine
Lymphatic (aka immune)
Digestive
Reproductive

Question 15

Define the function of the digestive system.

Answer 15

Takes in nutrients, breaks them down, and eliminates unabsorbed matter.

Question 16

Define the function of the respiratory system.

Answer 16

Takes in oxygen and eliminates carbon dioxide.

Question 17

Define the function of the cardiovascular system.

Answer 17

Distributes oxygen and nutrients (via the blood) to all body cells; delivers wastes and carbon dioxide to disposal organs.

Question 18

Define the function of the urinary system.

Answer 18

Eliminates nitrogenous wastes and excess ions. Regulates water, electrolyte, and acid-base balance of the blood.

Question 19

Define the function of the integumentary system.

Answer 19

Protects the body as a whole from the external environment.

Question 20

Define the function of the skeletal system.

Answer 20

Protects and supports body organs, and provides a framework the muscles use to cause movement.

Question 21

Define the function of the muscular system.

Answer 21

Allows manipulation of the environment, locomotion, and facial expression. Maintains posture and produces heat.

Question 22

Define the function of the nervous system.

Answer 22

The control system of the body; responds to internal and external changes by activating appropriate muscles and glands.

Question 23

Define the function of the endocrine system.

Answer 23

Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism).

Question 24

Define the function of the lymphatic system.

Answer 24

Disposes of debris, returns fluid to the blood, houses immune cells. The immune response mounts the attack against foreign substances in the body.

Question 25

Define the function of the reproductive system.

Answer 25

Functions to produce offspring.

Question 26

Define the two types of metabolism.

Answer 26

Metabolism includes all chemical reactions that occur within body cells.
CATABOLISM involves breaking down substances into small building blocks.
ANABOLISM involves synthesising more complex substances from simpler building blocks.

Question 27

Define cellular respiration.

Answer 27

The act of using nutrients and oxygen to produce ATP, the energy-rich molecules that power cellular activities.

Question 28

List the 5 survival needs of the human body.

Answer 28

Nutrients (food), oxygen, water, appropriate temperature, appropriate atmospheric pressure.

Question 29

Define homeostasis.

Answer 29

The ability of the body to maintain relatively stable internal conditions (within narrow limits). A dynamic state of equilibrium.

Question 30

Which two body systems are chiefly responsible for communication within the body.

Answer 30

Endocrine (bloodborne hormones) and nervous (neural electrical impulses).

Question 31

Discuss the three components of a homeostatic control system (a negative or positive feedback loop).

Answer 31

RECEPTOR - a sensor that monitors the environment. The receptor responds to stimuli (changes) by sending information (input) along the afferent pathway to the control centre.
CONTROL CENTRE - determines the set point (the level or range of levels where the variable is maintained). Analyses input by comparing it to the set point and determines the appropriate response. Information (output) travels along the efferent pathway to the effector.
EFFECTOR - carries out the control centre’s response to the stimulus. The results of the response then feedback, either reducing the stimulus to shut off the process (negative feedback), or enhancing it to fasten the process (positive feedback).

N.B. afferent pathways Approach the control centre, while efferent pathways Exit the control centre.

Question 32

Give an example of a homeostatic feedback loop.

Answer 32

The control of blood sugar (glucose) by insulin - as blood sugar rises, receptors in the body sense this change and the pancreas (the control centre) secretes insulin into the blood. This change prompts the body cells to absorb more glucose, removing it from the bloodstream. As blood sugar falls, the stimulus for insulin release ends.

Other examples include heart rate, blood pressure, the rate and depth of breathing, and blood levels of oxygen, carbon dioxide, and minerals.

Question 33

What is the impact of a positive feedback loop?

Answer 33

The initial response enhances the original stimulus so that further responses are even greater - the change that results proceeds in the same direction as the initial change, causing the variable to deviate further and further from its original value.

Examples include the enhancement of labour contractions during birth and blood clotting.

Question 34

Describe the anatomical position.

Answer 34

Standing erect with feet slightly apart (i.e., standing at attention), with the palms facing forward and the thumbs pointing away from the body.